Technical data

11.0 Fault finding
27
Does
the pilot
light ?
Does
the main
burner
light ?
Are
gas cocks
fully open ?
Is
pilot burner
clean ?
Is flue
blocked causing
A.S.D. to
operate ?
Is there
a spark at
electrode ?
Is
there power
to the
appliance
?
Is
gas supply
turned
on ?
START
Check electrode
lead and
insulation
Check power
supply
Correct
spark gap
(see diagram)
Clean
pilot burner
YES
YES
NO
YES
Is
meter
pressure
correct ?
(20mb)
Consult the
Gas Supplier
Turn on
gas supply
NO
NO
Fire
operating
satisfactorily
YES
YES
NO
NO
NO
YES
NO
YES
YES
NO
Has
On/Off
neon
illuminated
?
NO
Pilot supply
blocked -
replace gas valve
Is
meter pressure
correct ?
YES
YES
Is
pilot flame
stable and approx
20mm long
?
YES
Is
thermocouple
tip clean ?
YES
Is
thermocouple
tip sound ?
YES
Is
thermocouple
output correct ?
(6.5-10mV)
NO
Change
pilot assembly
Change the
control box
Rectify flue
NO
YES
Open
gas cocks
Contact the
Gas Supplier
Clean
thermocouple tip
Change
pilot assembly
NO
NO
NO
NO
YES
NO
NO
Are
thermocouple
connections
sound ?
Make good
the connection
NO
YES
Was
On/Off button
held for
3-4 seconds
?
YES
Restart ignition
sequence
Did
ignition
sequence
start ?
Fault on
control system
Is
spark gap
(2.5-4mm) ?
NO
NO
YES
YES
NO
Does
the fire modulate
high to low ?
Is neon
operating from
high to low ?
Does
illumination
effect work ?
Does
one bulb light ?
Is
there 11V
at bulb spade
connections ?
Fault on
control system
Change
transformer
assembly
Change
illumination
P.C.B.
NO
NO
YES
YES
Change bulb
YES
NO
Did
motorised valve
make noise ?
Do
illumination
bulbs light ?
YES
YES
Change motorised
gas valve
Change
transformer
assembly
Change
control box
NO
NO
Check connection
on switch at board
Pilot/A.S.D.
Assembly
2.5 - 4mm
Before starting Fault Finding carry out
preliminary electrical system checks i.e.
Earth Continuity, Polarity, Short Circuit and
Resistance to Earth.